1. Field of Invention
The invention relates generally to forming sheet material and in particular to a method and system for forming sheet material into multiple shapes.
2. Description of Related Art
Roll forming machines are used to form sheet material, such as steel, into structural elements. Common structural elements include C-shaped purlins and Z-shaped purlins such as those shown in FIGS. 1 and 2. The C-shaped purlins and Z-shaped purlins include a central section 10, legs 12 and lips 14. Other exemplary structural elements formed from sheet material include open C purlins, cave struts, etc.
It is desirable to form both C-shaped and Z-shaped members on a single machine. Attempts have been made to provide adjustable machines that convert from a C forming configuration to a Z forming configuration. One example is disclosed in U.S. Pat. No. 5,829,294 which discloses a roll former line in which a roll stand having three rollers is adjusted up and down in order to convert between C forming and Z forming configurations. A drawback to such designs is the time required to convert the machine from C forming to Z forming configuration. Thus, there is a need in the art for a convertible roll forming apparatus requiring little setup time.